A couple of years ago we were discussing bid adjustments by device on the weekly #ppcchat twitter tag, and I posted a screenshot to voice my frustration at the inability to split desktop and tablet traffic in my AdWords campaigns.

Others were equally frustrated by the inability to effectively target mobile only traffic - you had to implement a clumsy workaround which would reduce mobile traffic, but not eliminate it.

The solution seemed so simple - have a "base" bid and then allow all device types to have a bid adjustment - that you had to conclude that Google had simply decided that they knew best and that we were not going to able to filter our traffic the way we wanted to.

And then Google announced a change.

We are going to have bid adjustment by device. And not just any bid adjustment, but big, 4x4 bid adjustment running from -100% to completely eliminate traffic from a device to +900%.

And the guys on the @AdWords twitter account were quick to let me know - just a couple of days later, they replied to my tweet of 2014 where I bemoaned the lack bid adjustment options.

There is little doubt that Google know more about where the trends are heading than we lowly marketers - and they are very focussed on mobile traffic. Very, very focussed. And we should be paying attention. But oftentimes it seems that Google forget that whilst they are five years into the future, we are seven years behind them, and many of their core users are some years behind us.

It probably makes perfect sense for an engineer at Google to look at the significance of mobile advertising and where the customer is going to be. But this assumes that everyone else in the chain is keeping up.

If we, as Google recommend we do, put mobile first, this assumes that our client's website is mobile friendly - or, as a minimum, that there is a mobile version. Often this is way beyond the reality.

For the business that develops a solid mobile strategy, the potential gains are significant. For those that don't... well, they are no longer on anything even resembling a level playing field.

The new ability to adjust bids for different devices holds great optimisation promise. Unfortunately, many advertisers will simply take advantage of the options to eliminate mobile and tablet traffic. Or, maybe tablet and desktop. And if you are an app developer, you might eliminate desktop and mobile - and this might be the one case where that would be a sensible and justifiable configuration. But most advertisers would simply be taking the easy way out - eliminating traffic which they are ill-equipped to serve.

Bid adjustments can do much more than simply eliminate traffic. Unfortunately, for many, this will be all they use them for.